1. Field of the Invention
This invention relates to a projectile having improved accuracy. More particularly, the projectile has a hollow point, a fore portion with a near tangential ogive and an aft portion with a boattail. The projectile is machined from a monolithic block of a copper alloy.
2. Description of Related Art
Medium caliber cartridges, that have a projectile diameter of between 0.3 inch and 0.6 inch, are widely used in military and sporting applications. The projectiles are often fired from a weapon over long distances, in excess of 1000 meters, and require a high degree of accuracy to hit the target. For example, the present 0.50 caliber cartridge used by the United States military for sniper applications is the grade A, MK211, multi-purpose cartridge (MPC).
A disadvantage with the MPC is relatively high cost due to the use of a component made from tungsten carbide and the multiplicity of components within the bullet. There is a need for a cartridge having accuracy at least comparable to the MPC at ranges of up to 1500 meters that further does not decrease the useful life of the weapon, has a loaded length within the existing 0.50 caliber specification for use in weapons having box-type magazines and is less costly to manufacture than the MPC.
A monolithic copper alloy hunting bullet is disclosed in U.S. Pat. No. 4,685,397 to Schirneker that is incorporated by reference in its entirety herein. The projectile is machined from tombac, a copper alloy that typically contains between 10% and 20%, by weight, of zinc, and has an ogival nose portion with side walls that appear linear when viewed in longitudinal cross-section, a rear portion that angles inward, typically referred to as a boattail and a generally cylindrical mid-portion disposed between the fore and aft portions. A blind hole extends from an opening at the front end of the bullet to a point within the mid-portion. A steel insert then seals the front end of the blind hole.
The projectile disclosed in U.S. Pat. No. 4,685,397 is not believed to satisfy the accuracy requirements for a 0.50 caliber match grade cartridge because the generally linear side walls of the ogival nose portion will cause excessive free flight or jump to engagement with the rifling of the barrel and the relatively large, constant diameter, mid-portion will likely decrease the useful life of the weapon through erosion of the barrel.
There remains, therefore, a need for a medium caliber projectile that retains the accuracy of the 0.50 caliber grade A, MK211 MPC capable of low cost manufacture, and does not have the disadvantages specified above for the prior art.